ABSTRACT
The Lepidoptera are one of the largest groups of insects, comprising approximately 150,000 described species, about 94% of which are moths. Although moths are highly diverged in morphology and biology, most species use a common reproduction system that involves long-distance attraction of males with volatile chemicals, i.e. sex pheromones, produced by females. Because most moths are nocturnal, sex pheromone-mediated olfactory cues are a reliable tool for recognitions of conspecific mates. Conversely, diurnal insects may use visual signals instead of pheromones; diurnal insects generally have more conspicuous, with sexual dimorphisms in their wing or body patterns compared to nocturnal species. Recent studies on several diurnal moths, including clearwing moths, hawk moths, and Japanese nine-spotted moth, substantiated these moths use chemical signals which are common in other moths as well as visual cues with species-specific morphological features. Moreover, their pheromone chemicals are very useful and essential to understand their lifecycle, behavior, ecology, or evolution; by using synthetic copies of these pheromones, a rare or even a novel species can be discovered and monitored. This chapter reviews diurnal moth pheromone studies and show some examples of their potential applied uses for biodiversity assessment, conservation of the species in population declines, and environmental protection.
